The present invention relates to a base for reflection-photographic elements which are photographic elements that have photographic layers formed on bases made of opaque reflecting materials. Reflection-photographic elements typically include those which are generally referred to as "photographic papers".
Polyethylene-coated paper has been conventionally used as a base for reflection-photographic elements and it consists of pulp-made raw paper coated with a polyethylene layer containing a white pigment. One disadvantage of polyethylene-coated paper is that a reflection-photographic element using it as a base has a grained and rippled glossy surface due to the asperities of the surface of raw paper and this impairs greatly the brightness and sharpness of a photographic image and, hence, the aesthetic appeal that is desirably attained by these attributes. Another disadvantage is that although both sides of the base are coated with a water-impermeable polyethylene layer, the edges that are produced by cutting are uncoated and processing solutions such as developer will get into and remain in the base to cause discoloration of the final print.
In order to eliminate these disadvantages, Japanese Patent Application (OPI) No. 114921/1974, Japanese Patent Publication No. 5104/1980, British Patent Nos. 1,563,591, 1,563,592, Japanese Patent Publication No. 4901/1981, Japanese Patent Application (OPI) No. 118746/1986 and other patents have proposed bases for reflection-photographic elements that are made of thermoplastic resin films containing white pibments. Titanium dioxide, which has good hiding power, is preferred as a white pigment and polyester resins having properties suitable for photographic are preferred thermoplastic resins. Titanium dioxide compounds are available in two types, rutile and anatase. Rutile titanium dioxide has high weather resistance but is excessively yellowish in color. Anatase titanium dioxide is less yellowish but is not high in weather resistance and upon standing, especially in sunshine, it will turn yellow, and even dark brown, by decomposing the resins around the particles of titanium dioxide.